SLAM help

Chemchallenge

Member
Aug 9, 2019
6
Baytown
Ok I started having trouble with algae showing up every three day even after shocking and brushing the pool all my numbers were good except my CYA was off the chart.

Did a little research and figured that this was the problem. I drained about half the pool and refilled with community well water. Same water I started with and tested. There was a little algae but not too bad but there was no Chlorine. My alkalinity was high and my PH was at 7.7. I decided to SLAM my pool and read that I needed to get my PH down to 7.0-7.2 first.

I calculated how much muriatic acid to add using the pool math calculator which Inhave used successfully several times in the past.

So I add the prescribed amount 179oz. Poured in the pool slowly in front of the return jets and circulated the pool over night about 9 hours. When I sampled the PH went front 7.7-7.6 alkalinity was still high about 230. So I decided to let it circulate a little longer and test when I got home about 8 hours later. NO Change but the algae was getting worse. I added another 179oz and let it circulate over night. The next morning the algae was even worse and the PH was a 7.7. I added another 2 bottles and the algae is even worse and the PH is 7.5 but the alkalinity is 113.

What should I do my entire pool is green now and the algae on the walls is getting thick?
 

Donldson

TFP Expert
LifeTime Supporter
In The Industry
Jun 12, 2009
3,828
NW Ohio
The algae is getting worse because you haven't started to implement the SLAM Process yet. You are only adding acid, which doesn't kill algae.

How are you testing your water? SLAM requires personally testing with an FAS-DPD kit (TF-100 or Taylor k-2006c). A TA reading of 113 does not sound like one from a kit that fits the bill for this.
 

Chemchallenge

Member
Aug 9, 2019
6
Baytown
I haven’t added any chlorine because the SLAM procedure said to get the PH down to 7.0-7.2 first. SomI was trying to follow that procedure.

I’m using a LaMotte ColorQ Pro7 Liquid Test kit.
 

Donldson

TFP Expert
LifeTime Supporter
In The Industry
Jun 12, 2009
3,828
NW Ohio
Well my opinion of the accuracy ColorQ aside (for now), how do you plan to SLAM when it cannot read above 10 ppm FC?

Have you added any chlorine in the past few days?
 

frogabog

Gold Supporter
LifeTime Supporter
Jul 16, 2010
2,472
Portland, Oregon
Your pool volume may be incorrect. If you use the browser version of Pool Math, you can backwards calculate your additions and results. Play with the pool volume field till you get matching results. It's a little easier to do this with chlorine than acid though.

You really do need a proper test kit if you're going to SLAM. See Test Kits Compared.
 

Chemchallenge

Member
Aug 9, 2019
6
Baytown
Ok so I ordered the TF100 test kit bundle last night. I also added 10 x 128 oz 10% liquid chlorine. Pool is still green tonight but most of the algae seems like greenish yellow dust.

I tested the water tonight and here are my results.

FC 2.84
TC 2.60
PH 7.5
ALK 203
CH 83
CYA 49

I am thinking I need to brush and add more liquid chlorine. What else?
 

mknauss

Mod Squad
TFP Expert
Bronze Supporter
May 3, 2014
21,297
Laughlin, NV
Welcome to the forum!
Add 5 ppm FC worth of liquid chlorine each evening with the pump running until you receive your test kit.